This invention relates to oil filter assemblies. More particularly, this invention relates to modular relief valve and anti-drainback valve subassemblies of the type utilized in oil filters for automotive engines.
As there are a variety of filter requirements for meeting various automotive engine specifications, there are also numerous valve requirements for various automotive filters. In some heavy duty applications, it has been customary to utilize clean-side as well as dirty-side anti-drainback valves in conjunction with typical oil pressure relief valves employed in most applications. Most often, the dirty-side anti-drainback valve and relief valve structures are entirely separate, although arranged in close proximity to each other. However, when employed, clean-side anti-drainback valves have typically been manufactured as mechanically integral parts of the relief valve structures; hence, modular assembly or disassembly of the typical combined relief valve and clean-side valve structures has not been feasible. To the extent that modular units of such valves could be formed or constructed as "subassemblies", a resultant benefit would be greater inventory flexibility. Thus, relief valve modules would normally be installed within each originally manufactured automotive filter, while modular clean-side anti-drainback units could be conveniently subsequently installed, as or if required, without necessity of stocking compound or dual valve units as such.